1. Field of the Invention
The present invention relates to a battery module, to a battery module system, and a method for preventing damage that is caused by a battery.
2. Description of the Prior Art
In batteries, such as lithium-ion batteries, which in general are disposed in battery modules, disruptions can occur. Disruptions in batteries have manifold causes, which are often a succession of improperly occurring electrochemical reactions in the batteries. Lithium-ion batteries contain oxidants, such as LiCoO2 and oxidizable materials, such as ethylene carbonate. These materials are separated from one another by a thin polymer membrane, which withstands a maximum temperature of 180° C. At higher temperatures than 180° C., because of a disruption or overcharging or undercharging of the battery, the oxidant and the oxidizable materials reach one another and react exothermically with one another, so that the temperature in the battery increases still further.
In general, batteries with a disruption are able only to output or receive or store less electrical current, if any. Moreover, because of the disruption, the electrical internal resistance of the batteries is generally increased, and/or the poles of the battery become transposed. The result of the disruption is often destruction of the battery with exothermic processes, so that the result is a major heat development and the occurrence of gases or vapors that can escape from the battery. For this purpose, batteries normally have overpressure valves, which beyond a certain pressure carry the gases or vapors out of the battery. The thermal and possibly chemical emissions escaping from the battery with the disruption can cause damage to other batteries and even destroy them, so that a destructive chain reaction between the batteries can occur. The gases and vapors that occur are in some cases highly poisonous, so that they can harm human beings.
Melting elements are known that beyond a certain temperature of the battery disconnect the battery from the electrical current-carrying lines. The melting elements are based on the physical process of melting a metal, beyond the melting temperature of the metal. Despite an electrical shutoff of the battery, poisonous gases and vapors can emerge from the battery, which can lead to considerable damage to the environment. For instance, humans can suffer damage to their health as a result.